The Role of Toll-Like Receptors and Nuclear Factor κB p65 Protein in the Pathogenesis of Otitis Media

The role of Toll-like receptor 4 (TLR4) and nuclear factor κB p65 (NF-κB p65) proteins in the pathogenesis of otitis media is explored. In recent years, the incidence of otitis media has been rising globally, becoming a significant threat to human health. More and more studies have found that Toll-like receptor 4 (TLR4), as a member of the Toll-like receptor family, can promote the generation of inflammatory factors and is closely related to the body’s immune response and inflammatory response. Nuclear factor-κB p65 (NF-κB p65) is a nuclear transcription factor that can interact with various cytokines, growth factors, and apoptotic factors, participating in processes such as oxidative stress, apoptosis, and inflammation in the body [1]. This article elaborates on the structure, function, and signaling pathways of TLR4 and NF-κB p65 proteins in the pathogenesis of otitis media, aiming to provide more precise targets and better therapeutic efficacy for the diagnosis and treatment of otitis media. The role of inflammation in disease.

中药单体治疗脊髓损伤后神经炎症:核转录因子κB信号通路的作用

背景:基于核转录因子κB通路探究神经炎症的靶向治疗越来越值得探究,中药靶点多、范围广、机制丰富及不良反应少等优点在治疗各类疾病时都具有十分巨大的潜力。目的:基于核转录因子κB信号通路,对近年研究中出现的山奈酚、红花黄、汉黄芩苷及雷公藤甲素等中药单体治疗脊髓损伤后神经炎症的研究进展进行系统的阐述与归纳。方法:以“脊髓损伤,炎症,抗炎,中药单体,单体化合物,NF-κB信号通路,黄酮,糖苷,酚类,酯类,生物碱”为检索词在中国知网数据库中进行检索;以“Spinal cord injury,inflammation,anti-inflammatory,traditional Chinese medicine monomer,monomeric compound,NF-κB signaling pathway,flavonoids,glycosides,phenols,esters,alkaloids”为检索词在PubMed数据库中进行检索,最终共纳入67篇文献进行综述分析。结果与结论:①核转录因子κB信号通路在神经系统中的作用复杂多样,能够调控中性粒细胞、小胶质细胞、星形胶质细胞和巨噬细胞等,介导损伤后炎症的发生与发展;②中药单体如汉黄芩苷对核转录因子κB抑制蛋白的降解、红花黄素对核转录因子κB信号通路磷酸化过程的抑制、山奈酚对核转录因子κB信号通路p65核易位的抑制等作用可以降低炎症反应对机体造成的影响,从而促进神经功能恢复;③核转录因子κB信号通路在损伤早期能够促进炎症反应和免疫细胞迁移活化,在损伤中后期能够促进损伤部位的修复和纤维化的发生等,适当的激活核转录因子κB信号通路具有促进炎症因子的释放、提高细胞的抗氧化能力及促进免疫细胞的活化等能力,但过度激活的核转录因子κB信号通路则容易导致慢性炎症的发生和持续、细胞凋亡受到抑制等;④未来的研究可以进一步探索如何准确调控核转录因子κB信号通路的活化水平、如何实现对神经系统炎症和损伤的精准干预展开,也可围绕中药单体的制备及中药单体对信号通路的作用机制展开,以期为神经系统疾病的康复和功能恢复提供更有效的治疗策略。

Nuclear factor kappa B: A marker of chemotherapy for human stage Ⅳ gastric carcinoma

AIM： To detect the nuclear factor kappa B （NF-κB） condition in human stage IV gastric carcinoma patients and to explore the correlation between NF-κB activation and survival of these patients after chemotherapy. METHODS： Expression of NF-κB-p65 was determined by immunohistochemical analysis. Activity of NF-κB DNA-binding in carcinoma tissue was detected by electrophoretic mobility shift assay. Kaplan-Meier survival analysis was performed to show the relation between NF-κB and progression-free survival （PFS） or overall survival （OS） of the patients. RESULTS： The positive expression rate of NF-κB-p65 in 60 gastric cancer tissue samples was 76.7% （46160）. The expression of NF-κB-p65 was reduced in adjacent carcinoma and normal tissue samples. Electrophoretic mobility shift assay （EMSA） analysis showed a strong activation of NF-κB in cancer tissue samples. A survival difference was found in NF-κB-p65 positive and negative patients. NF-κB-p65 expression was negative in cancer tissue samples （n = 14）. PFS was 191.40 ± 59.88 d and 152.93 ±16.99 d, respectively, in patients with positive NF-κB-p65 expression （n = 46） （P = 0.4028）. The survival time of patients with negative and positive NF-κB-p65 expression was 425.16 ±61.61 d and 418.85 ±42.98 d, respectively （P = 0.7303）. Kaplan-Meier analysis showed no significant difference in PFS or OS. The 46 patient tissue which positive NF-κB-p65 expression was found in the tissue samples from the 46 patients whose PFS and OS were 564.89 ± 75.94 d and s 352.37 ±41.32 d, respectively （P = 0.0165）. CONCLUSION： NF-κB is activated in gastric carcinoma tissue, which is related to the OS after chemotherapy.

Role of nuclear factor kappa B in central nervous system regeneration

Activation of nuclear factor kappa B （NF-κB） is a hallmark of various central nervous system （CNS） pathologies. Neuron-specific inhibition of its transcriptional activator subunit RelA, also referred to as p65, promotes neuronal survival under a range of conditions, i.e., for ischemic or excitotoxic insults. In macro- and microglial cells, post-lesional activation of NF-κB triggers a growth-permissive program which contributes to neural tissue inflammation, scar formation, and the expression of axonal growth inhibitors. Intriguingly, inhibition of such inducible NF-~B in the neuro-glial compartment, i.e., by genetic ablation of RelA or overexpression of a trans- dominant negative mutant of its upstream regulator IκBa, significantly enhances functional recovery and promotes axonal regeneration in the mature CNS. By contrast, depletion of the NF-κB subunit p50, which lacks transcriptional activator function and acts as a transcriptional repressor on its own, causes precocious neuronal loss and exacerbates axonal degeneration in the lesioned brain. Collectively, the data imply that NF-κB orchestrates a multicellular pro- gram in which κB-dependent gene expression establishes a growth-repulsive terrain within the post-lesioned brain that limits structural regeneration of neuronal circuits. Considering these subunit-specific functions, interference with the NF-κB pathway might hold clinical potentials to improve functional restoration following traumatic CNS injury.

Tumor metastasis and the reciprocal regulation of heparanase gene expression by nuclear factor kappa B in human gastric carcinoma tissue

AIM: To investigate whether NF-kB is activated in human gastric carcinoma tissues and, if so, to study whether there is any correlation between NF-kB activity and heparanase expression in gastric carcinoma. METHODS: NF-kB activation was assayed by immunohistochemical staining in formalin-fixed, paraffin-embedded specimens from 45 gastric carcinoma patients. Electrophoretic mobility shift assay (EMSA) method was used for nuclear protein from these fresh tissue specimens. Heparanase gene expression was quantified using quantitative RT-PCR. RESULTS: The nuclear translocation of RelA (marker of NF-kB activation) was significantly higher in tumor cells compared to adjacent and normal epithelial cells [(41.3±3.52)% vs (0.38±0.22) %, t=10.993, P= 0.000<0.05; (41.3±3.52)% vs(0±0.31)%, t=11.484, P= 0.000<0.05]. NF-kB activation was correlated with tumor invasion-related clinicopathological features such as lymphatic invasion, pathological stage, and depth of invasion (Z= 2.148, P= 0.032<0.05; t = 8.758, P= 0.033<0.05; t = 18.531, P = 0.006<0.05). NF-KB activation was significantly correlated with expression of heparanase gene (r= 0.194, P=0.046<0.05). CONCLUSION: NF-KB RelA (p65) activation was related with increased heparanase gene expression and correlated with poor clinicopathological characteristics in gastric cancers. This suggests NF-kB as a major controller of the metastatic phenotype through its reciprocal regulation of some metastasis-related genes.

Up-regulation of intestinal nuclear factor kappa B and intercellular adhesion molecule-1 following traumatic brain injury in rats

AIM: Nuclear factor kappa B (NF-κB) regulates a large number of genes involved in the inflammatory response to critical illnesses, but it is not known if and how NF-KB is activated and intercellular adhesion molecule-1 (ICAM-1) expressed in the gut following traumatic brain injury (TBI). The aim of current study was to investigate the temporal pattern of intestinal NF-κB activation and ICAM-1 expression following TBI. METHODS: Male Wistar rats were randomly divided into six groups (6 rats in each group) including controls with sham operation and TBI groups at hours 3, 12, 24, and 72, and on d 7. Parietal brain contusion was adopted using weight-dropping method. All rats were decapitated at corresponding time point and mid-jejunum samples were taken. NF-KB binding activity in jejunal tissue was measured using EMSA. Immunohistochemistry was used for detection of ICAM-1 expression in jejunal samples. RESULTS: There was a very low NF-κB binding activity and little ICAM-1 expression in the gut of control rats after sham surgery. NF-KB binding activity in jejunum significantly increased by 160% at 3 h following TBI (P<0.05 vs control), peaked at 72 h (500% increase) and remained elevated on d 7 post-injury by 390% increase. Compared to controls, ICAM-1 was significantly up-regulated on the endothelia of microvessels in villous interstitium and lamina propria by 24 h following TBI and maximally expressed at 72 h post-injury (P<0.001). The endothelial ICAM-1 immunoreactivity in jejunal mucosa still remained strong on d 7 post-injury. The peak of NF-κB activation and endothelial ICAM-1 expression coincided in time with the period during which secondary mucosal injury of the gut was also at their culmination following TBI. CONCLUSION: TBI could induce an immediate and persistent up-regulation of NF-κB activity and subsequent up-regulation of ICAM-1 expression in the intestine. Inflammatory response mediated by increased NF-κB activation and ICAM-1 expression may play an important role in the pathogenesis of acute gut mucosal injury following TBI.

Effects of nuclear factor κB expression on retinal neovascularization and apoptosis in a diabetic retinopathy rat model

AIM: To investigate the expression and role of nuclear factor κB(NF-κB) in diabetic retinopathy(DR) and its relationship with neovascularization and retinal cell apoptosis. METHODS: A total of 80 male Wistar rats were randomly assigned to control(4, 8, 12 and 16 wk, n =10 in each group) and diabetes mellitus(DM) groups(4, 8, 12 and 16wk, n =10 in each group). A diabetic rat model was established by intraperitoneal injection of streptozotocin(60 mg/kg). After 4, 8, 12 and 16 wk, rats were sacrificed.Retinal layers and retinal neovascularization growth were stained with hematoxylin-eosin and examined under light microscopy. Cell apoptosis in the retina was detected by Td T-mediated d UTP nick end labeling, and NF-κB distribution and expression in the retina was determined using immunohistochemistry. RESULTS: DM model success rate up to 100%.Diabetes model at each time point after the experimental groupcompared with the control group, the blood glucose was significantly increased, decreased body weight, each time point showed significant differences compared with the control group(P 【0.01). After 12 wk other pathological changes in the retina of diabetic rats were observed; after 16 wk, neovascularization were observed. After 1mo, retinal cell apoptosis was observed.Compared with the control group, NF-κB expression in the DM group significantly increased with disease duration.CONCLUSION: With the prolonging of DM progression,the expression NF-κB increases. NF-κB may be related to retinal cell apoptosis and neovascularization.

Role of osteoprotegerin/receptor activator of nuclear factor kappa B/receptor activator of nuclear factor kappa B ligand axis in nonalcoholic fatty liver disease

Concomitantly with the increase in the prevalences of overweight/obesity, nonalcoholic fatty liver disease(NAFLD) has worldwide become the main cause of chronic liver disease in both adults and children. Patients with fatty liver display features of metabolic syndrome(Met S), like insulin resistance(IR), glucose intolerance, hypertension and dyslipidemia. Recently, epidemiological studies have linked obesity, Met S, and NAFLD to decreased bone mineral density and osteoporosis, highlighting an intricate interplay among bone, adipose tissue, and liver. Osteoprotegerin(OPG), an important symbol of the receptor activator of nuclear factor-B ligand/receptor activator of nuclear factor kappa B/OPG system activation, typically considered for its role in bone metabolism, may also play critical roles in the initiation and perpetuation of obesityrelated comorbidities. Clinical data have indicated that OPG concentrations are associated with hypertension, left ventricular hypertrophy, vascular calcification, endothelial dysfunction, and severity of liver damage in chronic hepatitis C. Nonetheless, the relationship between circulating OPG and IR as a key feature of Met S as well as between OPG and NAFLD remains uncertain. Thus, the aims of the present review are to provide the existent knowledge on these associations and to discuss briefly the underlying mechanisms linking OPG and NAFLD.

Inhibition of p38 mitogen-activated protein kinase attenuates experimental autoimmune hepatitis: Involvement of nuclear factor kappa B

To investigate the role of p38 mitogen-activated protein kinase （p38MAPK） in murine experimental autoimmune hepatitis （EAH）.METHODS： To induce EAH, the syngeneic S-100 antigen emulsified in complete Freud＇s adjuvant was injected intraperitoneally into adult male C57BI/6 mice. Liver injury was assessed by serum ALT and liver histology. The expression and activity of p38 MAPK were measured by Western blot and kinase activity assays. In addition, DNA binding activities of nuclear factor kappa B （NF-KB） were analyzed by electrophoretic mobility shift assay. The effects of SB203580, a specific p38 MAPK inhibitor, on liver injuries and expression of proinflammatory cytokines （interferon-y, IL-12, IL-1β and TNF-α） were observed.RESULTS： The activity of p38 MAPK and NF-~：B was increased and reached its peak 14 or 21 d after the first syngeneic S-100 administration. Inhibition of p38 MAPK activation by SB203580 decreased the activation of NF-~：B and the expression of proinflammatory cytokines. Moreover, hepatic injuries were improved significantly after SB203580 administration.

Delayed hepatocarcinogenesis through antiangiogenic intervention in the nuclear factor-kappa B activation pathway in rats

BACKGROUND: The active form of nuclear factor-kappa B (NF-kappa B) is involved in the initiation, generation, and development of hepatocellular carcinoma (HCC), and is up-regulated in inflammation-associated malignancies. We investigated the dynamic expression of NF-kappa B and its influences on the occurrence of HCC through antiangiogenic (thalidomide) intervention in NF-kappa B activation. METHODS : Hepatoma models were induced with 2-fluorenylacetamide (2-FAA, 0.05%) in male Sprague-Dawley rats, and thalidomide (100 mg/kg body weight) was administered intragastrically to intervene in NF-kappa B activation. The pathological changes in the liver of sacrificed rats were assessed after hematoxylin and eosin staining. NF-kappa B mRNA was amplified by RT-nested PCR. The alterations of NF-kappa B and vascular endothelial growth factor (VEGF) expression were analyzed by enzyme-linked immunosorbent assay, immunohistochemistry, and Western blotting. RESULTS: Rat hepatocytes showed denatured, precancerous, and cancerous stages in hepatocarcinogenesis, with an increasing tendency of hepatic NF-kappa B, NF-kappa B mRNA, and VEGF expression, and their values in the HCC group were higher than those in controls (P<0.001). In the thalidomide-treated group, the morphologic changes generated only punctiform denaturation and necrosis at the early or middle stages, and nodular hyperplasia or a little atypical hyperplasia at the final stages, with the expression of NF-kappa B (chi(2)=9.93, P<0.001) and VEGF (chi(2)=8.024, P<0.001) lower than that in the 2-FAA group. CONCLUSION: NF-kappa B is overexpressed in hepatocarcinogenesis and antiangiogenic treatment down-regulates the expression of NF-kappa B and VEGF, and delays the occurrence of HCC. (Hepatobiliary Pancreat Dis Int 2010; 9: 169-174)

Effects of ketamine on proinflammatory cytokines and nuclear factor kappaB in polymicrobial sepsis rats

AIM： To explore the effects of ketamine on hemodynamics, plasma proinflammatory cytokine （TNF-α and IL-6） levels and nuclear factor kappa B （NF-κB） activation during polymicrobial sepsis. METHODS： Male Sprague-Dawlay rats were subjected to cecal ligation and puncture （CLP） or sham operation. The rats were randomly assigned into four equal groups： sham CLP group, CLP group, ketamine （KT）Ⅰ group and KTⅡgroup. Thirty minutes before CLP, ketamine （5 mg/kg per hour and 10 mglkg per hour, respectively） was infused continuously through the left femoral vein cannula in KT Ⅰ group or KTⅡgroup. Sham CLP group and CLP group received 0.9% saline only （5 mL/kg per hour）. The right femoral artery was cannulated to monitor mean arterial pressure （MAP） and heart rates （HR）,and draw blood samples. The proinflammatory cytokine （TNF-α and IL-6） levels of plasma were measured using enzyme-linked immunosorbent assays （ELISA）. The hepatic NF-κB activation was determined by Western blot and HPIAS 2000 image analysis system. Twenty hours after CLP, the rats were killed by right femoral artery phlebotomization. RESULTS： CLP produced progressive hypotension, and a first increase followed by a decrease in HR. The hypotension was prevented, and the HR was slightly steady in ketamine treated rats. TNF-α levels of plasma reached a peak value at 2 h after CLP. Ketamine （KT Ⅰ group or KTⅡgroup） caused a significant decrease compared with CLP group at 2, 5 and 9 h time points after CLP （14.3 ± 1.9 vs 4.3 ± 0.9, 9.7 ± 1.4 vs 4.3 ± 0.9; 9.3 ± 1.5 vs 4.3 ± 0.9, 8.7 ± 1.4 vs 4.3 ±0.9; 6.0 ± 1.5 vs 5.0 ± 1.7, 5.3 ± 0.8 vs 5.0 ± 1.7; P 〈 0.01, respectively）. The IL-6 levels of plasma firstly ascended and then descended in CLP group, and reached a peak value at 9 h after CLP. Ketamine （KT I group or KTH group） caused a significant decrease compared with CLP group at 5, 9 or 20 h after CLP （135.0 ± 52.6 vs 60.0 ± 16.3, 112.5 ± 52.6 vs 60.0 ± 16.3; 410.0 ± 68.7 vs 62.5 ± 12.5, 250.0 ± 28.0 vs 62.5 ± 12.5; 320.0 ± 25.9 vs 52.5 ± 10.1, 215.0 ± 44.6 vs 52.5 ± 10.1; P 〈 0.05, respectively）. The IL-6 levels of plasma in KTⅡgroup were lower than those of KT Ⅰ group at 9 h after CLP （250.0 ± 28.0 vs 410.0 ± 68.7; P 〈 0.05）. In addition, CLP increased hepatic NF-κB expression compared with sham CLP. Ketamine suppressed NF-κB activation in a dose-dependent manner at 4 h after CLP （237.7 ± 3.5 vs 246.9 ± 3.1; P 〈 0.05）. CONCLUSION： Ketamine stabilizes the hemodynamics, attenuates the proinflammatory cytokine responses, and inhibits hepatic NF-κB activation. These findings suggest that ketamine has protective effects against polymicrobial sepsis in rats.

Urinary trypsin inhibitor attenuates hepatic ischemia-reperfusion injury by reducing nuclear factor-kappa B activation

BACKGROUND: Urinary trypsin inhibitor (UTI) inhibits the inflammatory response and protects against ischemia-reperfusion (I/R) injury. The inflammatory response is mediated by nuclear factor-kappa B (NF-kappa B) and its related target genes and products such as vascular endothelial cell adhesion molecule and CXC chemokines. We aimed to assess the roles of those mediators in a UTI-treated mouse model of hepatic I/R injury. METHODS: Treatment group 1 (UTI given 5 minutes prior to liver ischemia), treatment group 2 (UTI given 5 minutes after the anhepatic phase) and a control group were investigated. Blood and liver samples were obtained and compared at 1, 3, 6 and 24 hours after reperfusion. RESULTS: Attenuation of pathological hepatocellular damage was greater in the treatment groups than in the control group (P < 0.05). Compared with the control group, the UTI treatment groups showed significantly lower serum alanine aminotransferase and aspartate aminotransferase levels, decreased myeloperoxidase activity, and reduced NF-kappa B activation. Also downregulated was the expression of tumor necrosis factor-alpha, cytokine-induced neutrophil chemoattractant, and macrophage inflammatory protein-2 at the mRNA level. P-selectin protein and intercellular adhesion molecule-1 protein expression were also downregulated. In addition, the treatment group I showed a better protective effect against I/R injury than the treatment group 2. CONCLUSIONS: UTI reduces NF-kappa B activation and downregulates the expression of its related mediators, followed by the inhibition of neutrophil aggregation and infiltration in hepatic I/R injury. The protective role of UTI is more effective in prevention than in treatment.

Characteristics of hepatic nuclear-transcription factor-kappa B expression and quantitative analysis in rat hepatocarcinogenesis

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors. We analyzed the expression of miclear-transcription factor-kappa B (NF-kappa B) during hepatocarcinogenesis in order to evaluate its dynamic expression and its clinical value in the development and diagnosis of HCC. METHODS: Hepatoma models were induced by oral administration of 2-acetamidoflurene (2-FAA) to male Sprague-Dawley rats. Morphological changes were observed after hematoxylin and eosin staining. The cellular distribution of NF-kappa B expression during different stages of cancer development was investigated by immunohistochemistry, and the level of NF-kappa B expression in liver tissues was quantitatively analyzed by ELISA. The gene fragments of hepatic NF-kappa B were amplified by nested-polymerase chain reaction assay. RESULTS: Hepatocytes showed vacuole-like degeneration during the early stages, then had a hyperplastic nodal appearance during the middle stages, and finally progressed to tubercles of cancerous nests with high differentiation. The NF-kappa B-positive material was buff-colored, fine particles localized in the nucleus, and the incidence of NF-kappa B-positive cells was 81.8% in degeneration, 83.3% in precancerous lesions, and 100% in cancerous tissues. All of these values were higher than those in controls (P<0.01). Hepatic NF-kappa B expression and hepatic NF-kappa B-mRNA were also higher during the course of HCC development (P<0.01). CONCLUSION: The NF-kappa B signal transduction pathway is activated during the early stages of HCC development, and its abnormal expression may be associated with the occurrence of HCC.

Effect of Helicobacter pylori cdrA on interleukin-8 secretions and nuclear factor kappa B activation

AIM： To investigate genetic diversity of Helicobacter pylori （H. pylorl） cell division-related gene A （cdrA） and its effect on the host response.METHODS： Inactivation of H. py/ori cdrA, which is involved in ceil division and morphological elonga- tion, has a role in chronic persistent infections. Ge- netic property of H. pylori cdrA was evaluated using polymerase chain reaction and sequencing in 128 （77 American and 51 Japanese） clinical isolates obtained from 48 and 51 patients, respectively. Enzyme-linked immunosorbent assay was performed to measure in- terleukin-8 （IL-8） secretion with gastric biopsy speci- mens obtained from American patients colonized with cdrA-positive or -negative strains and AGS cells co- cultured with wild-type HPK5 （cdrA-positive） or its de- rivative HPKT510 （cdrA-disruptant）. Furthermore, the cytotoxin-associated gene A （cagA） status （transloca- tion and phosphorylation） and kinetics of transcription factors [nuclear factor-kappa B （NF-~：B） and inhibition kappa B] were investigated in AGS cells co-cultured with HPK5, HPKT510 and its derivative HPKSCA （cagA- disruptant） by western blotting analysis with immuno- precipitation. RESULTS： Genetic diversity of the H. pylori cdrA gene demonstrated that the cdrA status segregated into two categories including four allele types, cdrA-positive （al- lele types, I and 11 ） and cdrA-negative （allele types; 111 and IV） categories, respectively. Almost all Japanese isolates were cdrA-positive （ 1 ： 7.8% and 11 ： 90.2%）, whereas 16.9% of American isolates were cdrA-positive （11） and 83.1% were cdrA-negative （nl： 37.7% and IV： 45.5%）, indicating extended diversity of cdrA in individual American isolates. Comparison of each isolate from different regions （antrum and corpus） in the stomach of 29 Americans revealed that cdrA status was identical in both isolates from different regions in 17 cases. However, 12 cases had a different cdrA al- lele and 6 of them exhibited a different cdrA category between two regions in the stomach. Furthermore, in 5 of the 6 cases possessing a different cdrA category, cdrA-negative isolate existed in the corpus, suggesting that cdrA-negative strain is more adaptable to coloni- zation in the corpus. IL-8 secretions from AGS revealed that IL-8 levels induced by a cdrA-disrupted HPKT510 was significantly lower （P 〈 0.01） compared to wild- type HPK5： corresponding to 50%-60% of those of wild-type HPK5. These data coincided with in vivo data that an average value of IL-8 in biopsy specimens from cdrA-positive and cdrA-negative groups was 215.6 and 135.9 pg/mL, respectively. Western blotting analysis documented that HPKT510 had no effect on CagA translocation and phosphorylation, however, nuclear accumulation of NF-κB was lower by HPKT510 com- pared to HPK5. CONCLUSION： Colonization by a cdrA-negative or cdrA-dysfunctional strain resulted in decreased IL-8 production and repression of NF-κB, and hence, atten- uate the host immunity leading to persistent infection.

BMS-345541 inhibited nuclear factor kappa B expression and improved locomotor function recovery in rats after acute spinal cord injury

This study sought to elucidate the changes of nuclear factor kappa B （NF-KB） expression and locomotor function of hind limb after subdural injection of BMS-345541 was applied in rats with acute spinal cord injury. The results indicated that BMS-345541 treatment reduced the expression of NF-kB at 24 hours after injury, compared with normal saline-treated rats. This treatment also led to a significant improvement in locomotor functional recovery at 14 days after injury. Overall, the findings demonstrated that BMS-345541 significantly ameliorated spinal cord injury-induced hind limb dysfunction by inhibiting the expression of NF-kB after spinal cord injury.

Receptor activator of nuclear factorκB ligand/osteoprotegerin axis and vascular calcifications in patients with chronic kidney disease

Vascular calcifications are commonly observed in patients with chronic kidney disease （CKD） and contri-bute to the excessive cardiovascular morbidity and mortality rates observed in these patients populations. Although the pathogenetic mechanisms are not yet fully elucidated, recent evidence suggests a link between bone metabolism and the development and progression of vascular calcifications. Moreover, accumulating data indicate that receptor activator of nuclear factor κB ligand/osteoprotegerin axis which plays essential roles in the regulation of bone metabolism is also involved in extra-osseous bone formation. Further studies are required to establish the prognostic significance of the above biomarkers as predictors of the presence and severity of vascular calcifications in CKD patients and of cardiovascular morbidity and mortality. Moreover, randomized clinical trials are needed to clarify whether inhibition of osteoclast activity will protect from vascular calcifcations.

High levels of homocysteine downregulate apolipoprotein E expression via nuclear factor kappa B

AIM: To investigate the effect of high homocysteine(Hcy) levels on apolipoprotein E(apoE) expression and the signaling pathways involved in this gene regulation.METHODS: Reverse transcriptase polymerase chain reaction(RT-PCR) and Western blot were used to assess apo E expression in cells treated with various concentrations(50-500 μmol/L) of Hcy. Calcium phosphatetransient transfections were performed in HEK-293 and RAW 264.7 cells to evaluate the effect of Hcy on apoE regulatory elements [promoter and distal multienhancer 2(ME2)]. To this aim, plasmids containing the proximal apoE promoter [(-500/+73)apoE construct] alone or in the presence of ME2 [ME2/(-500/+73)apoE construct] to drive the expression of the reporter luciferase gene were used. Co-transfection experiments were carried out to investigate the downstream effectors of Hcymediated regulation of apoE promoter by using specific inhibitors or a dominant negative form of IKβ. In other co-transfections, the luciferase reporter was under the control of synthetic promoters containing multiple specific binding sites for nuclear factor kappa B(NF-κB), activator protein-1(AP-1) or nuclear factor of activated T cells(NFAT). Chromatin immunoprecipitation(ChI P)assay was accomplished to detect the binding of NF-κB p65 subunit to the apoE promoter in HEK-293 treated with 500 μmol/L Hcy. As control, cells were incubated with similar concentration of cysteine. NF-κB p65 proteins bound to DNA were immunoprecipitated with anti-p65 antibodies and DNA was identified by PCR using primers amplifying the region-100/+4 of the apoE gene. RESULTS: RT-PCR revealed that high levels of Hcy(250-750 μmol/L) induced a 2-3 fold decrease in apoE m RNA levels in HEK-293 cells, while apo E gene expression was not significantly affected by treatment with lower concentrations of Hcy(100 μmol/L). Immunoblotting data provided additional evidence for the negative role of Hcy in apoE expression. Hcy decreased apoE promoter activity, in the presence or absence of ME2, in a dose dependent manner, in both RAW 264.7 and HEK-293 cells, as revealed by transient transfection experiments. The downstream effectors of the signaling pathways of Hcy were also investigated. The inhibitory effect of Hcy on the apo E promoter activity was counteracted by MAPK/ERK kinase 1/2(MEK1/2) inhibitor U0126, suggesting that MEK1/2 is involved in the downregulation of apoE promoter activity by Hcy. Our data demonstrated that Hcy-induced inhibition of apoE took place through activation of NF-κB. Moreover, we demonstrated that Hcy activated a synthetic promoter containing three NF-κB binding sites, but did not affect promoters containing AP-1 or NFAT binding sites. ChI P experiments revealed that NF-κB p65 subunit is recruited to the apoE promoter following Hcy treatment of cells.CONCLUSION: Hcy-induced stress negatively modulates apoE expression via MEK1/2 and NF-κB activation. The decreased apo E expression in peripheral tissues may aggravate atherosclerosis, neurodegenerative diseases and renal dysfunctions.

Role of Nuclear Transcription Factor-кB in Endotoxin induced Shock in Rats

Summary: To investigate the role of NF-κB in endotoxic shock in rats, the model of endotoxin-shock rats was induced by intravenous infusion of lipopolysaccharide (LPS). 1 h, 2 h, 4 h and 6 h after LPS injection, the activation of NF-κB in blood mononuclear cells and the content of TNF-α and IL-6 in plasma was detected by enzyme-linked immunoadsordent assay (ELISA). The level of mean arterial pressure (MAP) and the histopathological changes of lung and liver were also observed. The activation of NF-κB in mononuclear cells increased 1 h after LPS injection and reached its peak 2 h after the injection, and its level was higher than that of normal group. The level of TNF-α was increased 1 h after the infusion and peaked 2 h after the injection, and its level was higher than that of normal group after LPS infusion. The content of IL-6 increased gradually with time, the IL-6 level was higher than that of normal group after LPS injection. MAP was decreased gradually with time and its level was lower than that of normal group after LPS injection. Pathological examination showed that endotoxic shock could cause pulmonary alveolar hemorrhage, edema and infiltration of inflammatory cell in lung tissue and congestion, edema, capillary dilation and inflammatory cell infiltration in liver tissue. It is concluded that NF-κB can up-regulate the expression of TNF-α and IL-6 in plasma and play an important role in endotoxin-induced shock in rats.

Effects of L-3-n-butylphthalide on caspase-3 and nuclear factor kappa-B expression in primary basal forebrain and hippocampal cultures after beta-amyloid peptide 1-42 treatment

BACKGROUND： L-3-n-butylphthalide （L-NBP） can inhibit phosphorylation of tau protein and reduce the neurotoxicity of beta-amyloid peptide 1-42 （Aβ1-42）. OBJECTIVE： To observe the neuroprotective effects of L-NBP on caspase-3 and nuclear factor kappa-B （NF- K B） expression in a rat model of Alzheimer＇s disease. DESIGN, TIME AND SETTING： A cell experiment was performed at the Central Laboratory of Provincial Hospital affiliated to Shandong University between January 2008 and August 2008. MATERIALS： L-NBP （purity 〉 98%） was provided by Shijiazhuang Pharma Group NBP Pharmaceutical Company Limited. Aβ1-42, 3-[4,5-dimethylthiazolo-2]-2,5 iphenyltetrazolium bromide （MTT）, and rabbit anti-Caspase-3 polyclonal antibody were provided by Cell Signaling, USA; goat anti-choactase and rabbit anti-NF- kB antibodies were provided by Santa Cruz, USA. METHODS： Primary cultures were generated from rat basal forebrain and hippocampal neurons at 17 or 19 days of gestation. The cells were assigned into five groups： the control group, the Aβ1-42 group （2 μmol/L）, the Aβ1-42 ＋ 0.1 μmol/L L-NBP group, the Aβ1-42 ＋ 1 μ mol/L L-NBP group, and the Aβ1-42 ＋ 10μmol/L L-NBP group. The neurons were treated with Aβ1-42 （2 μmol/L） alone or in combination with L-NBP （0.1, 1, 10 μmol/L） for 48 hours. Cells in the control group were incubated in PBS. MAIN OUTCOME MEASURES： Morphologic changes were evaluated using inverted microscopy, viability using the M-I-I- method, and the changes in caspase-3 and NF- k B expression using Western blot. RESULTS： Induction with Aβ1-42 for 48 hours caused cell death and soma atrophy, and increased caspase-3 and NF- K B expression （P 〈 0.05）. L-NBP blocked these changes in cell morphology, decreased caspase-3 and NF- k B expression （P 〈 0.05）, and improved cell viability, especially at the high dose （P 〈 0.05）. CONCLUSION： AI3^-42 is toxic to basal forebrain and hippocampal primary neurons; L-NBP protects against this toxicity and inhibits the induction of caspase-3 and NF- K B expression.

Hepatocyte nuclear factor 1B mutation in a Chinese family with renal cysts and diabetes syndrome:A case report

BACKGROUND Renal cysts and diabetes(RCAD)syndrome is an autosomal dominant diabetic renal disease.Precise molecular diagnosis of RCAD syndrome has proven valuable for understanding its mechanism and personalized therapy.CASE SUMMARY A RCAD patient and her family were studied to investigate potential responsible genes by the whole exome sequencing(WES).Candidate pathogenic variants were validated by Sanger sequencing.The clinical characteristics of RCAD patient were collected from medical records.Unlike those typical RCAD patients,we observed renal manifestation and prediabetes phenotype,but not reproductive organ phenotype and hypomagnesaemia.A novel 7-bp deletion mutation in exon 4 of the hepatocyte nuclear factor 1B,NM_000458:c.882_888del(p.V294fs),was identified by WES and confirmed by Sanger sequencing.CONCLUSION This novel mutation identified in a Chinese family with RCAD syndrome might be the molecular pathogenic basis of this disorder.